Fuel delivery systems for gas turbine engines typically contain many complex components. For example, a fuel delivery system can include a flowmeter that provides fuel to a shut off valve, which controls delivery of fuel to flow divider circuitry. The flow divider circuitry adjusts the distribution of fuel to the fuel nozzles while the total fuel flow is measured by the flowmeter. Gas turbine engines on aircrafts are generally operated under two conditions: low flow and high flow. Low flow conditions include for example ground idle and descent, and high flow operations include take off and cruise.
The flow divider valve enables unequal fuel flow to the fuel nozzles during specific conditions and equal fuel flow during other conditions. For example, equal flow may be provided to the fuel nozzles during high flow operations and unequal flow may be provided during low flow operations. The unequal flow to fuel nozzles of the combustor provides for some quadrants of the combustor to be at a higher pressure than other quadrants. This creates a fixed standing pressure wave in the combustor plenum and prevents a rotating pressure wave from occurring. A rotating wave is undesirable because it creates an intense acoustic tone known as howling.
Current fuel delivery systems are expensive and heavy. Additionally, the current fuel flow delivery systems are complex and typically require complex control systems.